Cars, trucks, and sports utility vehicles are frequently used as towing vehicles to transport towed vehicles, such as trailers. Towed vehicles are often supported by a frame attached to the towing vehicle. A portion of the frame may extend beyond the body of the towed vehicle, toward the towing vehicle. This portion, called the tongue, is usually formed by connecting two pieces of the towed vehicle frame at a predetermined angle. A frame coupler often attaches to the tongue of the towed vehicle. The frame coupler is sized and shaped to connect to a portion of the towing vehicle.
Jack assemblies have long been used with towed vehicles, such as trailers. Typically, a jack assembly is secured to a towed vehicle and assists in stabilizing the towed vehicle while it is detached from a towing vehicle. For example, a jack assembly may be mounted to the towed vehicle tongue or directly to the frame coupler. The jack assembly may include a handle or other components to facilitate vertical movement of an outer tube with respect to an inner tube to raise and lower the jack assembly.
Jack assemblies can experience high handle torque forces, eventually resulting in galling of the inner and outer tubes. Such galling is prevalent in the area where the outer diameter of the inner tube and inner diameter of the outer tube contact each other while the jack assembly cycles up and down under load.
Standard jack assembly tubing sizes typically are designed with just enough clearance between the tubes to provide easy telescopic movement, but do not have more clearance than what is necessary for basic movement of the jack assembly. This minimal clearance does not allow for a bushing or buffering material between the tubes, which may result in such galling.
Moreover, jack assemblies typically include one or more wheels, casters, or footplates to allow for movement of the towed vehicle and/or engagement with the ground. Commonly, however, jack assemblies do not have wheels, casters or footplates that are capable of effectively handling the maximum loads or stresses for which the jack assembly is designed. Cost limitations and other restrictions prevent the current market offerings from providing a premium castering of a jack assembly. Accordingly, the castering of jack assemblies may limit the overall load capacity of the jack assembly.
Therefore, there is a need for a jack assembly that generally does not incur such galling between the inner and outer tubes. Further, there is a need for a jack assembly that includes a castering assembly that is capable of effectively handling the loads or stresses for which the jack assembly is designed while being cost efficient to manufacture. Still further, there is a need for a jack assembly that may provide improved functionality of prior art systems.